Plea: Kate and Gerry McCann asked David Cameron for help in finding Maddy

Scotland Yard is to ask Prime Minister David Cameron if he wants to continue funding an inquiry into the disappearance of Madeleine McCann. 

Met Commissioner Bernard Hogan-Howe is seeking a new commitment from the Government on financing  the “investigative review” of the McCann case.

The force launched the new inquiry 15 months ago after Mr Cameron responded to a plea from Madeleine’s parents Kate, 43, and Gerry McCann, 42. Detectives are examining all the evidence from the Portuguese inquiry into the child’s disappearance from her parents’ holiday flat in Praia da Luz in Portugal in 2007.

The girl, who was three at the time, vanished as her parents were having dinner with friends nearby.

Police say that so far the Government has provided an open cheque to fund the review, which has included the cost of translating police documents and witness statements as well as the cost of officers travelling to Portugal and Spain.

A team of 28 homicide detectives and seven civilian staff are engaged in the full-time review and so far it is thought the inquiry has cost about £2.5 million. 

Mr Hogan-Howe said he would be seeking a decision from the Government in the next few months over how long they wished to fund the investigation. He said police were still sifting through a huge cache of documents. However, the Portuguese authorities are still refusing to re-open the inquiry.

He said: “We are still reviewing a lot of material. It is a significant amount of money and we have quite a lot of officers tied up in this.

“There will be a point at which we and the Government will want to make a decision about what the likely outcome is.

“The Prime Minister agreed to fund this. We have not had any pressure to say you must stop spending more than x amount, we have received a lot of support. But by Christmas I would want a very clear view of what work is outstanding and what timeline there is for that.”

Mr Hogan-Howe’s comments are the first to suggest that there may be a limit on how long police spend on the case. Previously he has said there was no limit on the amount of time and manpower for the inquiry.

The official Portuguese inquiry was formally shelved in July 2008 but the Met opened a review of the case, Operation Grange, in May last year.

By April this year they had managed to look at a quarter of some 40,000 pieces of information.

Hopes were raised this year when Det Chief Insp Andy Redwood, leading the review, said he believed Madeleine had been abducted by a stranger and could be alive.